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861.
Guang-Cai Li Xu-Ling Qin Huai-Hua Song Ying-Ni Li Yu-Yan Qiu Shi-Chang Cui Yong-Sheng Wang Hui Wang Jun-Ling Gong 《Journal of cellular physiology》2019,234(12):22331-22342
Ovarian cancer characterizes as the fourth leading consequence of death associated with cancer for women. Accumulating evidence underscores the vital roles of microRNAs (miRNAs) in preventing ovarian cancer development. Besides, induction of the phosphatidylinositol-3 kinase/serine/threonine kinase (PI3K/Akt) pathway associated with the ovarian cancer cell migration and invasion. The study aims to examine the effects of miR-15b on the proliferation, apoptosis, and senescence of human ovarian cancer cells by binding to lysophosphatidic acid receptor 3 (LPAR3) with the involvement of the PI3K/Akt pathway. The positive expression of LPAR3 protein was detected by immunohistochemistry. Then the interaction between miR-15b and LPAR3 was examined. The possible role of miR-15b in ovarian cancer was explored using gain- and loss-of-function experiments. Subsequently, the functions of miR-15b on PI3K/Akt pathway, proliferation, migration, invasion, senescence and apoptosis of ovarian cancer cells were assessed. Furthermore, in vivo tumorigenicity assay in nude mice was performed. LPAR3 was overexpressed, whereas miR-15b was poorly expressed in ovarian cancer tissues. LPAR3 is a direct target of miR-15b. Restored miR-15b promoted Bax expression, apoptosis, and senescence, inhibited expression of LPAR3 and Bcl-2, the extent of PI3K and Akt phosphorylation, as well as ovarian cancer cell proliferation, migration, and invasion. Further, tumor growth was observed to be prevented by miR-15b overexpression. Collectively, our study demonstrates that miR-15b represses the proliferation and drives the senescence and apoptosis of ovarian cancer cells through the suppression of LPAR3 and the PI3K/Akt pathway, highlighting an antitumorigenic role of miR-15b. 相似文献
862.
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864.
Kai Chen Yu Yuan Ziyi Wang Dezhi Song Jinmin Zhao Zhen Cao Junhao Chen Qiang Guo Li Chen Jennifer Tickner Jiake Xu 《Journal of cellular physiology》2019,234(5):6477-6488
Excessive osteoclast formation and function are considered as the main causes of bone lytic disorders such as osteoporosis and osteolysis. Therefore, the osteoclast is a potential therapeutic target for the treatment of osteoporosis or other osteoclast-related diseases. Helvolic acid (HA), a mycotoxin originally isolated from Aspergillus fumigatus , has been discovered as an effective broad-spectrum antibacterial agent and has a wide range of pharmacological properties. Herein, for the first time, HA was demonstrated to be capable of significantly inhibiting receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis and bone resorption in vitro by suppressing nuclear factor of activated T cells 1 (NFATc1) activation. This inhibition was followed by the dramatically decreased expression of NFATc1-targeted genes including Ctr (encoding calcitonin receptor), Acp5 (encoding tartrate-resistant acid phosphatase [TRAcP]), Ctsk (encoding cathepsin K), Atp6v0d2 (encoding the vacuolar H+ ATPase V0 subunit d2 [V-ATPase-d2]) and Mmp9 (encoding matrix metallopeptidase 9) which are osteoclastic-specific genes required for osteoclast formation and function. Mechanistically, HA was shown to greatly attenuate multiple upstream pathways including extracellular signal-regulated kinase (ERK) phosphorylation, c-Fos signaling, and intracellular Ca 2+ oscillation, but had little effect on nuclear factor-κB (NF-κB) activation. In addition, HA also diminished the RANKL-induced generation of intracellular reactive oxygen species. Taken together, our study indicated HA effectively suppressed RANKL-induced osteoclast formation and function. Thus, we propose that HA can be potentially used in the development of a novel drug for osteoclast-related bone diseases. 相似文献
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868.
Pumo Cai Yunzhe Song Chuandong Yi Qiwen Zhang Huimin Xia Jia Lin Hehe Zhang Jianquan Yang Qinge Ji Jiahua Chen 《Entomologia Experimentalis et Applicata》2019,167(10):880-890
Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), the spotted wing drosophila, is a pest endemic to Southeast Asia that invaded the Americas and Europe in 2008. In contrast to most of its congeners, D. suzukii possesses a serrated ovipositor that allows it to lay eggs in unwounded commercial fruits, resulting in severe revenue losses for the industry. The purpose of this study was to determine the susceptibility of known host fruits, including cherry, strawberry, blueberry, and grape, and potential host fruits, such as banana and apple, to attack by D. suzukii. Based on the responses to volatile cues offered in a six‐choice olfactometer, the preference of female D. suzukii was ranked in the following order: strawberry = cherry > banana = apple = blueberry = grape, but in no‐choice and choice oviposition tests, the preferences were ranked as follows: cherry > strawberry = blueberry > grape = banana > apple. Furthermore, we reconfirmed that D. suzukii mainly targets rotten fruit for feeding and ripe fruit for oviposition, and females preferred fruits with intensive mechanical damage. Based on developmental parameters, apple was the least suitable host. This study has implications for the control of D. suzukii, especially in mixed fruit orchards, by providing a promising avenue for exploiting behaviour‐based control tools and emphasizing the importance of phenology in host fruit susceptibility. 相似文献
869.
Shan Song Duojun Qiu Yonghong Shi Shuai Wang Xinbo Zhou Nan Chen Jinying Wei Ming Wu Haijiang Wu Huijun Duan 《Journal of cellular physiology》2019,234(9):16485-16502
Thioredoxin-interacting protein (TXNIP) is induced by high glucose (HG), whereupon it acts to inhibit thioredoxin, thereby promoting oxidative stress. We have found that TXNIP knockdown in human renal tubular cells helped prevent the epithelial-to-mesenchymal transition (EMT). Here, we studied the potential effect of TXNIP on podocyte phenotypic alterations in diabetic nephropathy (DN) in vivo and in vitro. In conditionally immortalized mouse podocytes under HG conditions, knocking down TXNIP disrupted EMT, reactive oxygen species (ROS) production, and mammalian target of rapamycin (mTOR) pathway activation. Further, Raptor short hairpin RNA (shRNA), Rictor shRNA, and mTOR specific inhibitor KU-0063794 were used to assess if the mTOR signal pathway is involved in HG-induced EMT in podocytes. We found that Raptor shRNA, Rictor shRNA, and KU-0063794 could all restrain HG-induced EMT and ROS production in podocytes. In addition, antioxidant Tempol or N-acetylcysteine presented a prohibitive effect on HG-induced EMT in podocytes. Streptozotocin was utilized to render equally diabetic in wild-type (WT) control and TXNIP −/− (TKO) mice. Diabetes did not increase levels of 24-hr urinary protein, serum creatinine, blood urea nitrogen, and triglyceride in TXNIP −/− mice. Podocyte phenotypic alterations and podocyte loss were detected in WT but not in TKO diabetic mice. Oxidative stress was also suppressed in diabetic TKO mice relative to WT controls. Also, TXNIP deficiency suppresses the activation of mTOR in glomeruli of streptozotocin-induced diabetic mice. Moreover, TXNIP expression, mTOR activation, Nox1, and Nox4 could be detected in renal biopsy tissues of patients with DN. This suggests that decreased TXNIP could ameliorate phenotypic alterations of podocytes via inhibition of mTOR in DN, highlighting TXNIP as a promising therapeutic target. 相似文献
870.
Luo Wentao Zuo Xiaoan Griffin-Nolan Robert J. Xu Chong Ma Wang Song Lin Helsen Kenny Lin Yingchao Cai Jiangping Yu Qiang Wang Zhengwen Smith Melinda D. Han Xingguo Knapp Alan K. 《Plant and Soil》2019,434(1-2):343-361
Plant and Soil - Mechanisms by which soil pH affects rice growth await further elucidation. We have used a Systems Biology approach to elucidate the nature of the damage caused by extreme pH to... 相似文献